An Individual Retirement Account (IRA) is a trust that holds assets purchased with a taxpayer's earned income for the taxpayer's eventual benefit in old age.  A common investment asset within an IRA is a mutual fund.  Earnings and growth within the IRA accumulate there.  Withdrawals from the IRA are taxed only at the time of withdrawal, although some (in Roth IRAs) may never be taxed.  An IRA can be transferred from one administering firm to another, with an accompanying change of mutual fund, with no tax consequences.  This is a barest-bones description.  For more information, talk to your financial advisor, or see sources such as Wikipedia, Investopedia, and IRS Publication 590.